1. Field of the Invention
This invention relates to polyacrylamide gels as used in slab gel electrophoresis.
2. Description of the Prior Art
Slab gels are particularly useful for electrophoresis in view of their ability to accommodate multiple sample analyses and the ease with which the electropherograms can be observed and read by simply identifying the locations of the various bands on the gels that correspond to the individual components. Polyacrylamide is a gel material that is widely used in slab gels.
Slab gels are frequently supplied in pre-cast form, retained between two flat transparent plates in a cassette. The plates are typically made of plastic, and a difficulty that has been observed is an apparent distortion of the solute bands due to irregularities in the gel pore size near the interface between the gel and the plastic. These irregularities are detrimental to the electrophoretic analysis since the pore size affects the migration of the solute bands, and pore size variations cause distortions of the bands.
Polyacrylamide gels are formed from acrylamide monomers and bis-acrylamide crosslinkers by free radical reactions, and molecular oxygen is known to inhibit free radical formation and thereby to limit the growth of the polyacrylamide chain. The problem is particularly acute with polyacrylamide gels formed in plastic enclosures.